1.) Field of the Invention
The present invention relates to figure surface point generation and, more particularly, to generating surface points which form surface boundaries or surface contours of two or three dimensional figures in, for example, a two dimensional space.
2.) Description of the Prior Art
Representing three dimensional figures in a two dimensional space is common, for example, in Computer Aided Design (CAD), Computer Aided Manufacturing and the like. Typical CAD systems include a microcomputer coupled to an input device (e.g., a keyboard), an output device (e.g., a video display), and to a memory for storing suitable instructions and data for generating surfaces, plane or solid figures other graphics and the like.
Some known CAD techniques employ nonuniform rational B-splines (NURBS) and other modeling techniques which permit describing virtually any type of curves or curved surface, from simple 2-D circles to complex, doubly curved sculptured surfaces. See, for example, GEOMETRIC MODELING, by Michael E. Mortenson, (John Wiley & Sons, N.Y., 1985); CURVES AND SURFACES FOR COMPUTER AIDED GEOMETRIC DESIGN, by Farin, G., (Academic Press, San Diego, 1988); COMPUTER AIDED DESIGN, Piegel and Tiller, (November 1987, Vol. 19; and U.S. Pat. Nos. 5,119,309, FEATURE BASED METHOD OF DESIGNING AUTOMOTIVE PANELS, Jun. 2, 1992, Cavendish et al; 4,999,789, METHOD AND APPARATUS FOR TRIMMING B-SPLINE DESCRIPTIONS OF PATCHES IN A HIGH PERFORMANCE THREE DIMENSIONAL GRAPHICS SYSTEM, Mar. 12, 1991, James Flasconaro; 4,864,520, SHAPE GENERATING/CREATING SYSTEM FOR COMPUTER AIDED DESIGN, COMPUTER AIDED MANUFACTURING, COMPUTER AIDED ENGINEERING AND COMPUTER APPLIED TECHNOLOGY, Sep. 5, 1989, Setoguchi et al; 4,631,690, MULTIPROCESSOR COMPUTER SYSTEM FOR FORMING A COLOR PICTURE FROM OBJECT ELEMENTS DEFINED IN A HIERARCHIC DATA STRUCTURE, Dec. 23, 1986, Cortbout et al, all of which examples are herein incorporated in their entireties by reference.
Although the prior art arrangements are useful, the present inventor believes that they have not been entirely satisfactory because they require extensive core data bases of stored surfaces (fundamental or otherwise) and/or very complicated interpolation polynomials to create boundary surfaces.
The present inventor believes that further improvements in methods for determining or generating surface points are achievable.